Owing to advantages of low cost, good flexibility, low operation voltage, and high quantum efficiency, conjugated polymer luminescent materials have become research hotspot worldwide for the past decades, particularly drawn great attention due to their wide application prospects in the field of light emitting diode. However, conjugated polymer materials still have a lot of shortcomings in device implementation process, such as short device service life, and fluorescence quenching caused by interaction among polymer molecules. At the same time, routine spinning method for preparing polymer luminescent film can not control film thickness and homogeneity, and thus leads to poor device stability and efficiency.
Double-metal hydroxide, also called layered double hydroxides (LDHs), is a novel multifunctional layered material, and has the advantages of ion-exchange ability and adjustable metal element of laminar layer, etc. By mechanically stirring in organic solvent, LDHs can be delaminated into highly dispersed single-layer nanosheet laminas which can be self assembled into supermolecule thin film via electrostatic force, hydrogen bond, or hydrophilicity/hydrophobicity. Therefore, molecular structural units with different functional characteristics can be assembled into orderly arranged microdevice with different functions and structures by this layer-by-layer self assembly method.
Inorganic/organic composite ultrathin film formed by alternating assembly of luminescent polymer with negative charges and LDHs is beneficial for achieving molecular-scale oriented arrangement and uniform dispersion of luminescent polymer molecules to eliminate fluorescence quenching, and is also beneficial for improving physical and chemical stability of luminescent polymer. Poly(p-phenylene) is an important organic polymer blue luminescent material with the characteristics of high quantum efficiency and high rigidity. But the research regarding ultrathin film formed by assembly of poly(p-phenylene) and LDHs has not been reported until now.